The clinical coincidence of hypertension, obesity and non insulin diabetes mellitus (NIDDM) has long been recognized. Increasing interest has also been recently focused on the possible role of insulin and insulin resistance in mediating this association. There is also evidence that hyperglycemia per se may have a role in the pathogenesis of hypertension and atherosclerosis in NIDDM patients. Glucose is a determinant to cellular ion homeostasis, promoting an increase of intracellular calcium and suppressing intracellular free magnesium and pH. Moreover, hyperglycemia promotes glycosilation of proteins and the consequent accumulation of advanced glycosilation end products in tissues. It has recently been suggested that iter is a cellular ionic basis for the clinical and epidemiological linkage of hypertension, left ventricular hypertrophy (LVH), obesity and non insulin dependent diabetes mellitus (NIDDM). These clinical conditions may be different expressions of a common underlying defect in ion handling, displayed by elevated cytosolic free calcium and suppressed free magnesium levels. Therapeutically, reversal of this excess free calcium accumulation and/or free magnesium deficit with ion specific agents, such as calcium channel blocker drugs, may thus ameliorate not only the elevated blood pressure of hypertension but also the concurrent cardiac, vascular and metabolic aspects of the hypertensive states.